Flow around bodies generates noise, which is detrimental in particular aerodynamic applications for example where low noise emissions are a design requirement. One such application where the level of noise emissions is important is in the design of commercial aircraft. Over the past decades engine noise has been significantly reduced, for example by the introduction of high-bypass ratio turbofan engines. However, maintaining the minimum engine ground clearance with such high-bypass ratio turbo fan engines results in longer landing gear. Thus, landing gear on commercial aircraft have been identified as major noise contributors during approach and landing. The design of a landing gear is primarily based on its structural and dynamic function. This complex geometric design gives rise to unsteady flow which leads to unwanted noise generation.
Fairings have been proposed as a means of reducing landing gear noise. For example, a noise reduction fairing for an aircraft landing gear is disclosed in WO 01/04003A1. Such noise reduction fairings at least partially shield downstream components such as struts stays and actuators from high-speed flow.
Embodiments of the present invention seek to provide improved or alternate noise-reduction apparatus for aircraft. Some embodiments may also reduce the noise generated by noise reduction fairings themselves.